Multi-protocol label switching (full name in English is: Multi-Protocol Label Switching, hereinafter simply referred to as “MPLS”) is a system based on fast data packet switching and routing, which realizes packet service fast forwarding, and provides the network data traffic capabilities such as routing, forwarding, switching and the like. A ring network based on the MPLS technology may be called as a MPLS ring, and a plurality of MPLS rings can intersect on one or more nodes and constitute a network structure of MPLS ring interconnection (hereinafter simply referred to as a “MPLS interconnected ring”), as shown in FIG. 1.
Logic paths for transmitting service streams among individual nodes in a MPLS ring may be implemented based on a label switching path (full name in English is: Label Switching Path, hereinafter simply referred to as LSP). A MPLS ring consists of a MPLS work ring (hereinafter simply referred to as “work ring”) and a MPLS protection ring (hereinafter simply referred to as “protection ring”), and the directions of the two rings are opposite each other, taking a direction of a specific service stream as a reference. According to the actual needs, each ring may establish a plurality of logic paths for transmitting service streams and assign different logic paths to different service streams. In practice, the work ring and the protection ring may also be identified with the labels. For example, the work ring or the protection ring may be identified by attaching a layer of label to an outer layer of the label identifying the logic path of the service stream. Thus, the work ring and the protection ring may also be implemented based on LSP.
In order to improve the reliability of transmission, the MPLS interconnected ring may be protected using a manner of service end-to-end automatic protection switching (full name in English is: Automatic Protection Switching, hereinafter simply referred to as APS). As shown in FIG. 1, in a normal state, after entering the MPLS interconnected ring, the service streams are forwarded according to the service labels. In FIG. 1, the work logic path for transmitting the service steams is B→C→D→I→H. If a fault occurs in an intersection node D, an end-to-end APS is triggered, and the service streams will be switched to a protection logic path B→A→F→G→H to be transmitted.
In the MPLS ring protection scheme as described above, it is necessary to assign bandwidths for the work ring of the MPLS ring and the protection ring of the MPLS ring, respectively, so that the protection of faults in the internal of the ring is realized. In the case, the actual bandwidth utilization rate is only 50%. Further, In the MPLS ring protection scheme as described above, in order to realize the end-to-end protection of cross-ring services, the work ring is required to assign the bandwidths for the work logic path and the protection logic path, respectively, on the basis of the bandwidth utilization rate of 50%, and only 25% of the link bandwidth is actually used for transmitting the services, which results in a reduction of the actual bandwidth utilization rate.